(1) Field of the Invention
The present invention relates to a flocculation-magnetic separation system which pours flocculant agents and magnetic powders into wastewater and treats the wastewater by flocculation-magnetic separation.
(2) Description of the Related Art
Water treatment by the flocculation-magnetic separation means a system in which flocculant agents and magnetic powders are poured into wastewater that is a target to be treated, magnetic flocks are generated by agitating the wastewater, and the magnetic flocks are recovered by magnetic force, whereby substances to be eliminated are eliminated from the wastewater, thus obtaining treated water. In this system, though the recovered flocks are discarded as industrial wastes, the magnetic powders contained in the flocks are also discarded together with the flocks, so that the cost of supplying the magnetic powders is increased. In addition, the amount of the recovered flocks discarded as the industrial wastes is increased and the cost of discarding the flocks causes the running cost of a device for flocculation-magnetic separation to be increased. As technologies for solving this problem, JP Hei 11-123399 and JP Hei 11-207399 describe prior arts in which sludges containing magnetic powders are broken down by hydrothermal reaction and volume-reduced.